1. Field of the Invention
The invention relates to a surgical stapling instrument, and more particularly to such an instrument which may be of a single-use, disposable nature.
2. Description of the Prior Art
While the stapling instrument of the present invention may have many applications, it is particularly adapted for use as a surgical stapling instrument and will, for purposes of an exemplary showing, be so described. The surgical stapling instrument of the present invention could be so constructed as to be reusable, as will be briefly discussed hereinafter. Nevertheless, it is particularly well adapted to be inexpensively produced as a single-use, disposable instrument, and for that reason will be so described herein for purposes of an exemplary showing.
Recently surgeons have come more and more to the use of surgical staples (sometimes referred to as staple sutures), rather than conventional thread sutures, for the closing of wounds or incisions in the skin or fascia of a patient. This is true in part because the use of surgical staples is a far easier procedure. Of even greater importance, however, is the fact that the use of surgical staples is very much faster. Thus, the time required for suturing can be substantially reduced, thereby reducing the length of time the patient must be maintained under anesthesia.
Prior art workers have developed various types of surgical stapling instruments, examples of which are taught in U.S. Pat. Nos. 3,618,842; 3,643,851; 3,717,294; 3,837,555 and 3,873,016. In general, the prior art surgical stapling instruments are complex in construction and expensive to manufacture. These instruments do not lend themselves well to be so constructed as to be disposable. Prior art surgical staplers generally require a replaceable cartridge for the staples and a portion of the force required to actuate these instruments is expended in shifting a staple from a row thereof within the cartridge to an anvil means prior to formation of the staple about the anvil means. As a result, some prior art surgical stapling instruments require upwards of 20 pounds force to form and implant a surgical staple.
In the above mentioned U.S. Pat. No. 4,109,844, a disposable surgical stapler is taught. This surgical stapler is provided with an anvil plate terminating at its forward end in a coextensive anvil surface and slidably mounting a row of staples. Means are also provided to constantly urge and advance the row of staples along the anvil plate to place a forwardmost staple of the row on the anvil surface to be formed by a staple driver. The staple driver is shiftable between a normal upper position above and closely adjacent the forwardmost staple on the anvil surface and a lower position wherein it implants and forms the forwardmost staple.
The present invention provides a disposable surgical stapling instrument which represents an improvement over that of the above mentioned U.S. Pat. No. 4,109,844. The surgical stapling instrument of the present invention contains substantially all of the advantages of the surgical stapler taught in the above mentioned U.S. Pat. No. 4,109,844, including being disposable, light weight, inexpensive to manufacture and requiring very little force to operate it. In addition, the surgical stapling instrument of the present invention is characterized by a unique surgical staple magazine assembly and a unique driver-driver actuator-trigger assembly.